undet. Bivalvia
From the collection of Yale Peabody Museum. Free to download, adapt and use — no permission needed.
Geological context: Late Cretaceous, Fox Hills Fm, Timber Lake Mbr. Collection locality: float, grass-covered bluffs on E and SE side of SD Rt. 65, and on E and W sides of draw, 1 mi N of Moreau River, Ziebach County, South Dakota, USA. Collected by Karl M. Waage, George Colton, 1951. IP number 590180; lot count 1; accn=IPA.07048; associatedwith=IP.590531,IP.590543,IP.590550,IP.590521,IP.590525,IP.590526,IP.590527,IP.590528,IP.590529,IP.590530,IP.590532,IP.590533,IP.590534,IP.590535,IP.590536,IP.590537,IP.590538,IP.590539,IP.590540,IP.590541,IP.590542,IP.590544,IP.590545,IP.590546,IP.590547,IP.590548,IP.590549,IP.590551,IP.590552,IP.590553,IP.590554,IP.590555,IP.590518,IP.590519,IP.590520,IP.590522,IP.590523,IP.590524.
Yale Peabody Museum’s own description